EGFR and asthma: To confirm the role of EGFR in our murine model of asthma, we firstly determined the expression and phosphorylation level of EGFR protein by immunohistochemistry (Fig. 1a–d), immunofluorescence (Fig. 1f–j) and EGFR mRNA by RT-PCR (Fig. 1e) in lung tissue from different treatment groups challenged with either OVA or PBS.